CVE-2021-20048
HighWhat is CVE-2021-20048?
A Stack-based buffer overflow in the SonicOS SessionID HTTP response header allows a remote authenticated attacker to cause Denial of Service (DoS) and potentially results in code execution in the firewall. This vulnerability affected SonicOS Gen 5, Gen 6 and Gen 7 firmware versions.
CVSS Vector Breakdown
CVSS 3.1Exploitable remotely over the network without requiring access to the local system.
No special conditions required. Exploit can be performed reliably and repeatedly.
Basic user account required (e.g. standard login without admin rights).
No user interaction required. Exploit runs without any victim action.
Exploiting the vulnerability only affects the vulnerable component itself.
Complete loss of confidentiality. All data on the component may be exposed.
Complete loss of integrity. Attacker can modify any file or data on the component.
Complete denial of service. The component becomes fully unavailable.
Known Affected Devices
FAQ
CVE-2021-20048 has a CVSS score of 8.8/10, rated as High. This is a high severity vulnerability and should be patched as soon as possible.
CVSS (Common Vulnerability Scoring System) rates vulnerability severity from 0.0 to 10.0. CVE-2021-20048 scores 8.8/10 (High). Scores 9.0–10.0 are Critical, 7.0–8.9 are High, 4.0–6.9 are Medium, and below 4.0 are Low.
The list of devices confirmed to be affected by CVE-2021-20048 is shown in the "Affected Devices" section above. Check your firmware version against the vendor security advisory and apply the latest patch.
Apply the latest firmware or software update from the vendor. Check the References section above for official advisories and patch notes. If no patch is available, consider disabling the affected feature or isolating the device from untrusted networks.